Disease-induced changes in Ganoderma lucidum microbiome co-occurrence patterns and assembly processes

From the paper

Abstract

Host-associated microbial communities significantly influence the growth, development, and health of hosts. Green mold disease (GMD), caused by Trichoderma spp., is one of the predominant diseases encountered during commercial cultivation of Ganoderma lucidum. However, few studies have explored the impact of GMD on the microbial community of G. lucidum. This study examined the bacterial, fungal, and protistan communities in bulk soil, hyphosphere soil, and G. lucidum endosphere using 16S, ITS, and 18S amplicon sequencing. We also explored the effect of GMD on community assembly, co-occurrence patterns, and potential mechanisms of Trichoderma spp. infection in G. lucidum. Our findings indicated that the microbial communities of healthy G. lucidum possess enhanced stability and resistance. Compared with healthy G. lucidum, the microbial community structure of diseased G. lucidum is more prone to the impact of deterministic processes. Additionally, we discovered that the co-occurrence network of diseased G. lucidum is more complex, and that diseased G. lucidum may recruit antagonistic bacteria (Pseudomonas ASV2 and ASV22) and consumer protists (Proleptomons ASV28 and Colpoda ASV240). We also examined the impact of G. lucidum polysaccharides and triterpenoids on the growth of Trichoderma, found that these extracts can be utilized by pathogens in vitro and are associated with microbial community changes, while notably promoting the growth of Trichoderma ganodermatigerum. In summary, this study revealed the important role of the host microbiome in G. lucidum GMD, offering valuable insights into the complex interactions among the host, bacteria, fungi, and protists, supporting the design of novel strategies for harnessing microbial resources to improve agricultural productivity and quality.